Pneumatic dilatation of Achalasia

If you cannot pass the endoscope beyond the narrowing at GOJ , reconsider your diagnosis and consider pseudo-achalasia

A thorough endoscopic examination is important, with particular attention given to the GOJ, where malignancy can simulate achalasia (pseudoachalasia).

It is very important that your diagnosis of achalasia is quite firm ideally with endoscopic, Barium swallow and manometry findings.

Quite high risk procedure (5% chance of perforation)- so discussion in the clinic with the patient is important while discussing the alternatives (Laparoscopic cardiomyotomy)

These patients are prone to aspirate particularly when regurgitation of old food is the predominant symptom.

The patient is advised to fast for at least 12 hours prior to the procedure +/- liquid diet for one or two days preceding the dilation

Procedure

Choice of balloon

A 30 mm balloon is used for a first dilatation. Subsequent dilatation may involve larger balloon- 35 and 40cm.
This are quite big sized balloon compared to standard stricture dilatation balloons- the idea being to rupture the muscle fibres.

Inflate the balloon before use to check for any leaks

We describe the OTW ( over the wire) achalasia balloon from Rigiflex™ II ( Boston Scientific)

Picture2 and 3: Wilson-Cook achalasia dilatation balloon and the inflation and luminal port

Another alternative is reusable balloon (shown below)

Picture4 and 5: Reusable achalasia dilatation balloon with the pressure gauge: the endoscope goes through the top end of the yellow tube and comes out below the balloon

Positioning the balloon across the LOS

A guidewire is passed through the biopsy channel of the endoscope into the stomach and the scope is withdrawn to the GOJ.

Note the distance between the incisors and the GOJ along the length of the scope.

The endoscope is then removed (taking care to maintain the position of the guidewire in the stomach- push/pull technique).

As an aid in initial placement, a marker (such as a paper tape/ tippex) can be placed on the shaft of the dilating catheter to correspond to the previously noted distance from the incisors to the GOJ.

This distance should be measured from the middle of the balloon on the dilating catheter.

The balloon and tip of the shaft is lubricated and passed over the previously placed guide wire until the marker is in place at the incisors- that means the midpoint of the balloon is now at GOJ.

Actual dilatation

Using fluoroscopy, the balloon is then gradually inflated with air, noting the position of the developing waist.

Inflation is achieved with a 50ml syringe attached to the balloon port with a 3 way stopcock ( one end to catheter, second to syringe and third port to the pressure gauge)

The balloon is inflated with air

Small adjustments usually have to be made in the position (deflating the balloon each time) to ensure that the waist occupies the centre of the balloon- balloon will slip downwards if you are too down and then you will have to exert a pull upwards and vice versa- called the cone effect

After a satisfactory position is obtained, the balloon is fully inflated (usually requiring about 120 mL of air).

The required pressure will be specified on the moulded junction- average 7-15 PSI

The balloon is kept inflated for 60 seconds, during which patients may be very uncomfortable- give pethidine or fentanyl 2 minutes before the dilatation

After the 60 seconds are over, the balloon is rapidly deflated.

Sudden disappearance of the waist is very suspicious of rupture

Thereafter, perform another full inflation for 60 seconds and again note the pressure required to obliterate the waist. This is usually less than the initial pressure

Another alternative is reusable balloon-

The scope here is passed through the balloon and then the scope is introduced beyond GOJ- a J manoeuvre confirms part of the balloon beyond the GOJ ( see picture)

The side catheter containing the inflation port is attached straight to a inflation device with a pressure gauge ( see picture)

Pressure of 200mm kept for 2minutes and then release

Aftercare:

The patient is observed for the next five to six hours during which serious complications, such as perforation would be obvious